The present invention is directed to a collapsed apparatus which can be readily expanded for placement about a ventilation duct in an attic or the like for containing insulation in a preferred configuration about the duct.
Because energy is becoming an increasingly scarce resource for both the heating and cooling of houses and similar structures and because such energy is becoming increasingly expensive, it is becoming increasingly important to insulate such structures in such a manner so as to prevent loss of any substantial amounts of heating and cooling to the ambient air. Current recommended insulation guidelines typically call for an insulating factor in the R30 to R38 range. An insulating factor of R38 effectively equates to approximately 12 inches of blown cellulose or fiberglass insulation. Consequently, most modern houses are constructed with approximately 12 inches of insulation within the attic structure above the ceiling of the top floor.
In addition to energy lost through walls and ceilings, there can also be a substantial loss of energy through the duct work which carries heating and/or cooling throughout a structure. In order to avoid such a loss, this duct work is often placed beneath the ceiling or between a lowered artificial ceiling and the attic in such a structure. Nevertheless, many structures do not have sufficient clearance to place the duct work in a protected location and even when the duct work can be placed below the ceiling, it is often aesthetically unpleasing.
Consequently, the duct work is often placed in the attic, especially when no basement is present to carry it. When such duct work is placed in an attic, it is usually placed over ceiling joists and is typically 6 inches or greater in diameter or thickness. Because part of the insulation in an attic is between the joist, only about 61/2 inches of insulation will extend above the ceiling joists in an attic having an overall bed of 12 inches of insulation. If the duct work is 6 inches in thickness, this means that only approximately a half inch of insulation will cover the duct work. Consequently, it is desirable to also fully insulate the duct work that is run through the attic with a 12 inch layer of insulation.
While it is desirable to provide a full layer of insulation for the duct work, it would be prohibitively expensive to place an insulating blanket of sufficient thickness to provide 12 inches of insulation for the duct work throughout the entire attic and it may also make it difficult to work in the attic for people needing access thereto. Therefore, it is desirable to provide a structure that contains additional insulation in the region immediately surrounding the duct work so that the duct work can have a proper insulating cover without spreading the insulation in a uniform layer throughout the attic.
Structures for containing insulation in this manner have previously taken the form of a fixed wall which is constructed with material such as boards and plywood and nailed to the ceiling joists to form a trough for the insulation covering the duct work. While such a constructed wall is effective in maintaining the insulation, it has a major drawback in that it requires a substantial period of time, labor and materials to construct. Most insulators are interested in maintaining labor costs as low as possible and wish to quickly apply the appropriate insulation coating to an attic. Consequently, it is desirable to have a structure that is pre-made of relatively simple and inexpensive materials that can be quite readily expanded when placed in an attic to form the desired structure to surround the duct work and provide a containment for insulation covering the duct work.